A bipolar differential pair based on transconductance devices with improved linearity and signal-to-noise ratio is described. The circuit of the invention comprises differential pairs of two sets of bipolar transistors connected in parallel. Each differential pair performs a transistor area ratio at emitter areas. The invention also includes a diode connected to the emitters of the transistors of the differential pairs. When the device areas are properly scaled, the range for the input voltage signal still allowing a linear output current equation increases by a factor of two for the prior art circuits. The improved signal-to-noise ratio as well as the improved linearity are implemented by connecting the diodes to the emitters of the transistors, and also having parallel differential pairs with scaled transistor areas with respect to each other. Selectable embodiments of the present invention also describe the use of level transition steps. The ratios required in this embodiment can be set by means of level switching transistors which enable the use of all the same circuit core transistors and diodes. Since all identical circuit core transistors and diodes are of minimal size, this reduces parasitics and extends the circuit's operating range at high frequencies.
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